I was originally planning to use Def Tech in wall/ceiling but they have been discontinued.

No I'm tentatively planning on TruAudio GHT-SUR-P. But...they are 16" long (cutout is 15.8' x 8') and I would prefer something more square in orientation.

I definitely don't want anything round. Rectangular or square.

Just seeing what you guys might recommend? I don't have access to all brands, no longer a Snap dealer